/Engine/Source/Runtime/Analytics/Analytics/Public/Interfaces/IAnalyticsPropertyStore.h
Adds or updates the specified key/value pair. If the key doesn't exist, the key/value pair is added. If the key already exists, the value is updated if the stored value and the specified value types match.EStatusCode::Successif the key was added or updated,EStatusCode::BadTypeif the value type did not match the current value type.
[EStatusCode](API\Runtime\Analytics\Interfaces\IAnalyticsPropertyStore\EStatusCode) Set ( const [FString](API\Runtime\Core\Containers\FString) & Key, int32 Value )